A severe runny nose with watery eyes and a sore throat is usually due to a cold or allergy, causing irritation and excess mucus. Drink warm fluids, do salt water gargles, and take steam to soothe your throat and clear your nose. Rest well and avoid dust, smoke, and cold air as they can worsen symptoms. A doctor may advise suitable cold or allergy medicines if needed, and most cases improve within a few days.